I. Field of the Invention
The present invention relates to powder compacting apparatus and, more particularly, to an apparatus which produces a compacted article within very close dimensional tolerances and with broken corners, beveled or radiused, between a face of the article and its side surfaces, for example.
II. Description of the Prior Art
The present invention is concerned with improved tooling for use in powder-compacting presses such as are disclosed in U.S. Pat. Nos. 3,826,559; 3,775,032; 3,730,659; 3,726,622; 3,645,658; 3,574,892; 3,561,056; 3,415,142; 3,344,213; and 3,328,840, all of which are assigned to the same assignee as the present application.
In the powder-compacting presses disclosed in the aforementioned U.S. patents, articls are compacted and formed in a single or multi-cavity die forming part of a punch and die set, with the finished articles being automatically ejected from the die cavities, picked up by a vacuum pick-up head, and conveyed into suitable receptacles. A work station positioner assembly, which is part of the press, is mounted linearly or angularly movable transversely over the die plate and carries a powder dispenser, an anvil and the pick-up head. The powder dispenser, which is supplied with powder from a primary powder supply means connected thereto by means of a flexible tubing or the like, is first positioned over the die cavity or cavities which are thus filled with powder as the punch or punches are displaced downwardly so as to draw a predetermined amount of powder into the die cavity or cavities. The powder dispenser is then removed from above the die cavity or cavities by the subsequent angular motion of the station positioner assembly, and the anvil is, in turn, positioned over the cavity or cavities. The anvil is clamped over the die cavity or cavities by means of a clamp supported above the anvil and actuated in timed relation with the movement of the punches. The anvil is held down with sufficient pressure to permit compaction of the powder against the anvil as a result of an upward motion of the punch or punches into the die cavity or cavities. The anvil is then removed from its position over the die cavity or cavities and is replaced by the pick-up head, as a result of a further linear or angular motion of the work station positioner across the face of the die plate. Each punch is displaced upwardly so as to bring its upper end in substantial flush alignment with the upper surface of the die plate, such that the finished compacted articles are ejected from the die cavity or cavities and picked up by the pick-up head for transfer to appropriate containers.
In U.S. Pat. Nos. 3,775,032, 3,826,599, 4,047,864, 4,061,452, 4,061,453 and 4,230,653, also assigned to the same assignee as the present application, tooling arrangements for compacting articles from powder material are described in which a mold cavity is defined partly by the end face of an upper punch projecting through an anvil element above the die cavity, partly by the die bore wall and partly by the end face of the lower punch.